This invention relates to improved, highly efficient processes for the preparation of tetrabromobisphenol-A.
Tetrabromobisphenol-A is one of the most widely used brominated flame retardants in the world. It is used extensively to provide flame retardency for styrenic thermoplastics and for some thermoset resins.
U.S. Pat. No. 5,527,971 (its Background of The Invention is incorporated herein as if fully set forth) discloses highly beneficial techniques for the continuous and batch production of tetrabromobisphenol-A without concomitant production of alkyl bromide. In addition, these techniques produce a tetrabromobisphenol-A product having good color and low hydrolyzables and ionics. The process yield is excellent.
As is always the case in commercial endeavors, it is desirable to provide for improvements which benefit process aspects and/or which give a superior product. Therefore, it is an object of this invention to provide for these ends.